Multiple beam microstrip array fed by Rotman lens

For future road-pricing-systems antennas with specially shaped radiation patterns are required to illuminate a well defined segment of the road. In this case, typically five antennas are used to control a single traffic-lane. In the paper a multiple beam microstrip array, fed by a Rotman lens has been developed which exhibits five independent scanned beams so that each traffic-lane can be covered with only one multiple-beam antenna